1. Field of the Invention
The present invention relates to an improved automotive exhaust products evacuating system and more particularly to an improved automotive exhaust products evacuating system to be used in association with a dynamometer, the evacuating system adapted to accomodate motor vehicles of varying sizes while maintaining optimal exhaust capabilities.
2. Description of the Prior Art
When a vehicle having an internal combustion engine is being repaired or undergoing diagnostic testing, it frequently becomes necessary to operate its engine in an enclosed or partially enclosed structure. The need to effectively evacuate the toxic and noxious fumes emitted by the engine of the vehicle is well established in the prior art.
U.S. Pat. No. 3,415,113 describes a vehicle exhaust handling system particularly adapted for use in conjunction with a chassis dynamometer utilized in garages, automotive diagnostic centers or like places. The system described therein essentially comprises a plurality of upwardly opening hinged shutters positioned in a parallel manner and located over a chamber provided in the floor of the testing center.
When the motor vehicle to be tested is positioned with its rear wheels to engage a pair of rollers comprising a part of the dynamometer, the rear end of the motor vehicle is generally disposed over the chamber provided in the floor. An operator of the diagnostic center selects a shutter in closest proximity to the exhaust tail pipe of the vehicle, and opens that shutter. The rest of the shutters generally remain in a closed position. The opened shutter is adjusted to an angular position relative to the floor which provides optimal evacuation of the exhaust gases. A fan operated exhaust device is connected to the chamber in the floor through a suitable duct. The exhaust fan causes rapid flow of air from the space within the diagnostic center through the opened shutter into the chamber. This air captures the bulk of the noxious exhaust gases emanating from the tailpipe of the vehicle.
A second chamber in communication with the exhaust device and covered by a grate is located in front of the dynamometer below the engine of the vehicle. The purpose of this second chamber and grate is to provide general ventilation and to remove exhaust fumes which may leak out from the engine of the vehicle. The airflow through this grate, however, is not adjustable.
An additional disclosure related to an automotive diagnostic system with automatic ventilation may be found in U.S. Pat. No. 3,207,055. Furthermore, additional disclosures relating in general to ventilation and louver systems may be found in U.S. Pat. Nos. 2,293,065, 511,296, 1,412,039 and 1,971,920.
The exhaust product handling system described in U.S. Pat. No. 3,415,113 offers some capability to adjust the air-flow for maximum entrainment of exhuast fumes depending upon the size of the vehicles to be tested. Nevertheless it suffers from the following disadvantages: In order to accomodate vehicles of varying sizes the number of shutters required is relatively large, thereby increasing the cost of manufacturing the system. Furthermore even a large number of shutters may be unable to accomodate some large sized recreational vehicles, or when associated with the dynamometer, vehicles with front wheel drive.
For the above stated reasons a need still exists for an economical, adjustable vehicle exhaust handling system providing optimal exhaust removing capabilities.